Early Warnings for Pyrocumulonimbus Development in Western North America Based on NUCAPS Thermodynamic Profiles

The US Naval Research Laboratory Marine Meteorology Division (NRL-MMD) is currently evaluating satellite-based soundings afforded by the NOAA Unique Combined Atmospheric Processing System (NUCAPS) instruments onboard the NOAA-20 satellites for developing an early-warning prediction of pyrocumulonimbus (pyroCb) development in Western North America, including Alaska. This presentation will examine the efficacy of NUCAPS-derived near-surface lapse rate and vapor pressure deficit, mid-troposphere moisture content, and instability parameters to facilitate early warning of pyroCb development. NRL-MMD is developing fire pixel clustering and NUCAPS filtering techniques to focus on specific wildfire events that are likely to produce pyroCb activity. A logistic regression algorithm is employed to evaluate probabilities of pyroCb development over a nowcasting (8-12 hour) time window. The overarching objective is to provide weather forecasters and firefighting agencies with a potentially invaluable resource to predict and evaluate hazards ensuing from convective cloud development over active wildfires. From a firefighter’s perspective, pyroCb activity can produce erratic wind behavior near the surface, dry lightning, and even tornados. Recent studies also reveal that pyroCb activity can inject large smoke plumes into the stratosphere, thus adding pollution that can circle the globe and impact climate.